Device for coating articles with glass, enamel, quartz, and metals



Feb. 8 1927.

M. U. SCHOOP/ DEVICE FOR COATING ARTICLES WITH cmss, ENAMEL, QUARTZ, ANDMETALS Filed Jan. 13, 1922 Patented Feb; 8, 1927.

UNITED STATES MAX ULRICH SCHOOP, OF ZURICH, SW'ITZERLAND.

DEVICEFOR COATING ARTICLES WITH Application filed January 13, 1922.Serial No.

Producing coatings by means of a metallic powder is generally carriedout by forcing a mixture of compressed air and a metallic powder-througha concentric oxyhydrogen flame. whereby the metallic particles areheated and fused. \Vith substances with a high melting point such asglass, quartz, platinum, tungsten and the like it has provedadvantageous to avoid heating the nitrogen contained in the compressedair that serves as conveying agent to the metallic particles and to useinstead of compressed air a com pressed gas which burns or sustains thecombustion intensively and heats the article to which the coating is tobe applied during the coating process. That is to say I use gassubstantially free from nitrogen. By

, this method which forms the subject matter of the present invention itis attained that the particles reach the article to be coated in aplastic or liquid state, whereby the article is not cooled down when thecoating is produced on it, as is the case. in the hitherto known processmentioned above, but is continuously heated. In carrying out the presentprocess it is assumed that the articles to be coated will standtemperatures which are not materially different from those of themelting points of glass, enamel or the like.

In applying a coating of enamel or glass it must be borne in mind thatthe flame used in heating or preheating the article must act as areducing agent as otherwise intimate contact between the article and thecoating is not ensured.

The accompanying drawing illustrates a constructional example of adevice for carrying into effect the process according to the invention.In this drawing:

Fig. 1 is a vertical longitudinal section through the device,

Fig. 2 is an end view of a stop valve with parts being shown in section.

Fig. 3 is a general arrangement view of the device.

The material to be used for coating, for instance pulverulent copper, isenclosed in a receptacle 1 into which a compressed gas, for instanceoxygen or hydrogen, is introduced by means of a conduit 2; thepulverulent copper is stirred and forced through the channel 3 into thenozzle 4.. The current of compressed gas utilized for conveying thematerial is controlled by means of a regu- GLASS, ENAMEL, QUARTZ, ANDMETALS.

529,040, and in Switzerland February 8, 1921.

lating screw 5 being screwed into the nipple 6. The gas current passesthrough the opening 7 provided in the regulating screw 5 and enters thechamber 9 by means of four apertures 8; itis then forced'from thechamber 9 through the annular gap 10 into the receptacle 1. The width ofthe gap 10 may be adjusted by turning the regulating screw 5, wherebythe intensity of the gas current can be regulated at will.

In order to attain a uniform supply of the material for producing thecoating to the nozzle & which material can also be in a liquid stateinstead of being pulverulent, a sieve 11 is arranged inside thereceptacle 1. 12 denotes a casting made for instance of aluminium. inwhich a stop cook 13 is arranged. The casting 12 and the stop cook 13are provided with three bores for the passage of gases, oxygen beingsupplied by means of conduit or hose 14 from a container 26, acombustible gas, for instance acetylene, illuminating-gas or hydrogen byhose 15 from a container 27 and a combustible gas being supplied by hose16 from a container 28. The gases supplied by the hoses 14 and 15 areconducted into the mixing chamber 17, from where the mixture of gaspasses through the annular channel 18 in order to burn at the end ofsaid channel in the shape of a concentric, very hot flame. The channel18 is formed by the nozzles 4; and 19. The combustible gas supplied between the hose 16 passes through the annular channel 20 which is formedbetween the nozzles 19 and 21. For sake of clearness the sectionillustrating the connection between the hose 16 and the annular channel20 in the casting 12 (Fig. 1) is not a vertical section but a radialsection turned into the vertical. The two nozzles 21 and 19 are providedwith flanges 24 and 25 respectively, a throwover nut 22 coacting withsaid flanges secures the nozzles 19 and 21 to the nozzle carrier 23. Thepulverulcnt copper conveyed by the current of con'ipressed gas into thenozzle 4 and from there into the flame is intensively heated in saidflame and projected against the surface to be coated. The

article to be coated is thereby continuously heated so that its surfaceis preserved against any oxidation during the coating. An effectivepreheating of the article to be coated is generally advantageous and isnecessary when producing coatings of glass,

' quartz and enamel. The pre-heating of the article can be easilyeffected by 'ineans of'the device illustrated.

By using a current of gas directed upwardly through the body ofpulverulent material I obtain the novel resultof carrying in the gasstream only the finer particles of the pulverulent material, and effecta thorough stirring of the materials to break up the loosely adheringlumps so that these lumps are separated by gravity and not carried tothe outlet valves to clog them.

I claim In a device for coating articles, particularly with glass,enamel, quartz, metals and the like, a receptacle for the pulverulentcoating material, adjustable means arranged at the bottom of said eceptacle for admitting a stream of compressed combustible gas, nozzlemeans, means for supplying oxygen and two combustible gases to saidnozzle means for producing a blow-pipe flame, means connected to the topof said receptacle for conveying the stream of gas and the materialsuspended therein to said nozzle means for projecting the material, theparticles of which are heated to a high temperature by the combustion ofthe conveying agent, to the article to be coated, and battle meansprovided above the body of material in said receptacle for attaining auniform suspension.

In testimony whereof I aflix my signature.

ULRICH SCHOOP.

